531 OF ENGINEERING FOKMULÆ.
Floating Mill-wheels.
Velocity of periphery of wheel = Velocity of
stream x ‘4.
Diameter of wheels generally from 12 to 15 feet.
Number of floats generally from 9 to 11.
Inclination of floats from radial line about 25ö
to 30°.
Depth of floats from 24 to 30 inches.
Dip of floats from 12 to 15 inches.
Not less than two floats should be immersed at
once.
Effective Power of Floating Mills.
V = Velocity of stream in feet per second.
W = Mean velocity of float in feet per second.
A = Immersed area of floats in square feet.
P = Horse-power. P = -0028 Vr A (V-®).
Note.—These wheels seem never to be made
with curved floats. Floats, if made of a some-
what similar form to those of Poncelet’s undershot
wheel, would probably give a greater effect.
Breast and Overshot Wheels.
h = Head of water in feet.
Q = Quantity of water in cube feet per minute.
P = Effective horse-power.
a 961 P ,
’ t? = ■—5— m low-breast wheels.
» ”0
„ 881 P,o
W----j— W high-breast wheels.
h 777 P .
w = —r m overshot wheels.
P = -00104 Q h in Jow-breast wheels.
I’ = ‘00113 (2/tin high-breast wheels,
Q — '00128 QA in overshot wheels.
2 m 2